1. Technical Field
This invention relates to chain covers mounted on a plurality of roller chains arranged in parallel so as to cover the top and sides of the roller chains and form a flat goods conveying surface between the roller chains, and a slat conveyor formed by the chain covers.
2. Background Art
A prior art chain cover of this type is disclosed in JP Patent laid-open publication 2001-315936. The chain cover shown in JP Patent laid-open publication 2001-315936 includes a top cover which is a flat plate having a length about equal to the chain pitch, and side covers hanging from both ends of the top cover. The side covers serve to cover both sides of the roller chain and each side cover is formed with a shaft hole in which one end of a coupling pin of the roller chain is received, a convexly arcuate front edge which is concentric with the shaft hole, a concavely arcuate rear edge which corresponds to the front edge, and a tapered guide surface which extends outwardly obliquely on the inner surface of the side cover below the shaft hole.
With this chain cover, the top cover for covering the top of a roller chain is supported by links of the roller chain, so that no load will be applied to each coupling pin, and such chain covers can be mounted on general-purpose roller chains on which the amount of protrusion of coupling pins from pin links is small, so that a flat conveying surface can be formed on the chains.
However, with such chain covers, a chain conveyor having a wide goods conveying surface cannot be formed, so that the application of the chain conveyor obtained is limited. Also, although the width of the goods conveying surface can be increased by extending both ends of the top covers sidewise, it is difficult to increase the width of the goods conveying surface drastically with this method because the length of the extended portion is limited to assure strength.